Lower Dietary Calcium Intake is Associated with a Higher Risk of Mortality in Korean Adults

Calcium, one of the most abundant minerals in the human body, has a pivotal role in human physiology. However, only a few studies have examined the association of dietary calcium intake with mortality in a population with low calcium intake.The aim of this study was to examine the association of dietary calcium intake with risk of all-cause and cause-specific mortality among Korean adults with low calcium intake.This study was a prospective cohort study.The analysis was conducted using data from 44,327 eligible Korean adults aged 19 years and older who participated in the Korea National Health and Nutrition Examination Survey 2007-2015. Dietary calcium intake was assessed using 1-day 24-hour recall data.The main outcomes of this study were mortality from all causes, cancer, cardiovascular disease, respiratory disease, and all other causes combined. The outcome was ascertained through linkage to the death registry compiled by Statistics Korea with the use of the resident registration number.Weighted Cox proportional hazard models were used to estimate the hazard ratios and 95% CIs of the all-cause and cause-specific mortality according to dietary calcium intake.During a mean follow-up of 7.28 person-years, 1,889 deaths were ascertained. After multivariable adjustment, the hazard ratios for all-cause mortality for the second quintile to the highest quintile of dietary calcium intake, respectively, compared with the first quintile were 0.86 (95% CI 0.73 to 1.00), 0.82 (95% CI 0.69 to 0.98), 0.85 (95% CI 0.69 to 1.03), and 0.78 (95% CI 0.64 to 0.96) (P for trend from the lowest to the highest quintile = .04). There were no statistically significant associations between dietary calcium intake and risk of mortality from cancer, cardiovascular, or respiratory disease.In this large prospective cohort study of Korean adults, lower dietary calcium intake was associated with a higher risk of all-cause mortality.